Liftoff to Learning: From Undersea to Outer Space

Description: This program describes a life science experiment
using jellyfish. Because of their small size and rapid growth cycle,
results of the experiment have provided scientists with a unique window
into the process of living things adapting to microgravity.

Subjects: Research on the effects of microgravity on
jellyfish.

Science Process Skills:Observing
Making Models

Science Standards:Physical Science
- Position and motion of objects
- Properties of objects and materials
Unifying Concepts and Processes
-Change, constancy, and measurement
- Evidence, models, and exploration
Life Science
-Structure and function in living systems
-Diversity and adaptations of organisms
-Regulation and behavior

With its June 5, 1991 liftoff, the STS-40 crew of the Space
Shuttle Columbia began an exciting mission to understand how living
things function in the microgravity environment of Earth orbit. Microgravity
is the floating effect that occurs on an orbiting space vehicle where
objects seem to be weightless because they, and the vehicle they are riding
on, are in freefall. Columbia's principle payload was the first
Spacelab mission devoted to life sciences research, Spacelab Life Sciences
1 (SLS-1). It consisted of the Spacelab long module mounted in Columbia's
payload bay. The pressurized, cylindrical module was 7 meters long
and 5 meters in diameter. It was packed with experimental apparatus and
medical instrumentation for use by the mission's seven-member crew.

Medical and life science experiments, flown on many Space Shuttle and
Skylab missions, have provided tantalizing clues to how the human body
adapts to microgravity in Earth orbit and what changes take place in the
body. But often missing from past studies were data on the interrelationships
of different body systems in microgravity. The Spacelab Life Sciences
1 mission sought to extend the understanding of the human body in microgravity
by conducting studies on seven major body systems. These systems were:
cardiovascular/cardiopulmonary, hematological, muscular, skeletal, vestibular,
immune, and renal-endocrine.

An important part of the SLS-1 mission included 2,478 jellyfish polyps
encased in flasks and bags filled with artificial seawater. They were
the subjects in an experiment entitled, "The-Effects of Microgravity-Induced
Weightlessness on Aurelia Ephyra Differentiation and Statolith
Synthesis."

The principle investigator of the experiment was Dr. Dorothy B. Spangenberg
of the Eastern Virginia Medical School (EVMS) in Norfolk, VA. Dr. Spangenberg
wanted to learn how microgravity influences the development of tiny jellyfish
ephyrae and their gravity receptors as well as the function of the gravity
receptors. Gravity receptors enable jellyfish to sense up and down. The
sensors have statoliths within them that are analogous to the otoconia
found in the inner ears of humans and other mammals. The jellyfish used
in Dr. Spangenberg's experiment were of the Aurelia aurita variety.

Early in the mission, crew members injected thyroxine or iodine into the
containers to induce the polyps to metamorphose into free-swimming ephyrae.
The tiny ephyrae were videotaped to observe their swimming motions for
later comparison with control groups on the ground. Upon their return
to Earth, scientists began studying the jellyfish to determine if any
differences occurred in jellyfish gravity receptors (sensors) that developed
in space from those that developed on Earth. (Note: The experiment was
followed with a second experiment on the International Microgravity Laboratory
mission that orbited Earth from July 8-23, 1994.)

Dr. Spangenberg and her team discovered that ephyrae developed during
the flight and were able to pulse and swim in space. Statoliths formed
in normal numbers in space-developed ephyrae but ephyrae from Earth lost
statoliths in greater numbers after nine days in space than did their
Earth-maintained controls. Ephyrae from Earth pulsed faster in space and
tended to circle or loop when swimming.

Description of Jellyfish: Jellyfish have special structures which
enable them to swim and orient. These are called gravity receptors, and
they resemble microscopic fingers. These structures have calcium crystals
at their tips called statoliths, which move when the animals and the gravity
receptors move. These sensitive structures provide positional information
to the animal based on the direction of gravity and whether the jellyfish
are tilted up or down. It is especially important to know whether statolith
crystals form normally in space, since humans have similar calcium-containing
crystals (otoconia) in their inner ears which help them maintain balance.
In humans, the crystals are not accessible for study during or following
spaceflight.

Why Send Jellyfish into Space? Very few studies have been made of
developing organisms in space. Jellyfish complete their development at a
warm temperature in six days. Many of the developing structures of jellyfish
resemble structures of humans, although they are less complicated. Therefore,
jellyfish may be used to predict events which may occur in embryos of more
complex life forms during spaceflight.

Purpose of Experiment: To determine the effects of microgravity on
the developing jellyfish in order to help us understand and prevent the
adverse effects of microgravity on biological organisms, including humans.
The experiment has also helped us understand how gravity influences development
and behavior on Earth. Studies made to determine whether microgravity causes
a decrease in the calcium content of the jellyfish and their statolith crystals
may help predict a similar calcium deficiency in astronauts. Otoconia crystals
are found in the inner ears of humans, but the effect of microgravity on
the crystals in humans has not been studied previously.

Procedure: Tiny, baby jellyfish were flown on the Space Shuttle in
plastic bags in an incubator. The jellyfish were induced before and during
flight to make tiny pulsing and swimming ephyrae from small, slow-moving
polyps. During flight, ephyrae developed on Earth (control group), and some
which developed in space (experiment group), were videotaped to learn whether
they pulsed or swam normally. Following landing, researchers compared the
flight and control groups to each other. They studied the development of
jellyfish structures, including statoliths; grew new jellyfish through budding;
and observed swimming or pulsing movements of ephyrae. (Note: For detailed
information on the results of the experiment, refer to the journal articles
listed in the reference section of this guide.)

The following activities can be used to demonstrate some of the concepts
presented in this videotape.

Designing For Spaceflight

Materials

Paper and pencils

Procedure

Challenge students to design a future Space Shuttle experiment using living
things as subjects. What animals or plants would the experiment attempt
to study? What would the experiment's hypothesis and research procedures
be? What would the experiment apparatus look like and how would it function?
How would the living things be cared for on the Space Shuttle? Students
should submit sketches and descriptions of their apparatus. If time is available,
students can construct working models.

Drill a hole in the ball and in the center of the wood block. Glue
and assemble the model as shown in the picture. Slide the block across
a smooth surface. What happens to the ball and why? How does this
relate to gravity receptors in jellyfish and in humans? What can you
do to the device to make it work vertically?

Construct 3-D models of the metamorphosis of Aurelia aurita jellyfish
from larvae to medusa. Refer to the reference section for information
on these stages or obtain a jellyfish life cycle chart from a science
supply catalog.

Note: Several science supply catalogs offer jellyfish for dissection
and mounted specimens for study. Live jellyfish may also be available
for salt water aquariums. If you do not find a section in the index
for jellyfish, look up Aurelia.

- Information on culturing live jellyfish in the classroom is available
by writing to: Dr. Dorothy Spangenberg Department of Pathology, Box 1980
Eastem Virginia Medical School Norfolk, Virginia 23501

Principle Investigator Biography

Dr.Dorothy B. Spangenberg (Ph.D.): Dorothy Spangenberg, Ph.D.,
principal investigator for the study of the effects of microgravity on the
development and behavior of jellyfish, is research professor in the department
of pathology at Eastem Virginia Medical School in Norfolk, Virginia. Dr.
Spangenberg received her bachelor and master degrees in zoology and her
Ph.D. in developmental biology from the University of Texas. Throughout
her 31-year career as a developmental biologist, Spangenberg has studied
various aspects of jellyfish structure and development. From 1962 to 1965
Spangenberg was a research associate in pathology at the University of Arkansas,
and from 1965 to 1966 she was an associate professor at Little Rock University,
Arkansas. Spangenberg was a research scholar at Indiana University from
1966 to 1969, and from 1969 to 1972, she conducted jellyfish experiments
at the University of Louisville School of Dentistry, Kentucky. Spangenberg
was a visiting associate professor in the department of molecular, cellular
and developmental biology at the University of Colorado, Boulder from 1972
to 1977. In 1977, Spangenberg joined the faculty at Eastern Virginia Medical
School. Since that time her research has been funded by the National Institute
of Health, the National Institute for Dental Research and Child Health and
Human Development, the Department of Energy, and NASA. She is a nationally
renowned expert on jellyfish and has published many articles on the development
of the organism.